Pluto has been puzzling us with its weirdly smooth surface, but if it’s the first Kuiper Belt Object we’ve visited, how did we know how many craters to expect in the first place? Here’s everything we’ve figured out about collisions in this chaotic area of our Solar System. »7/28/15 2:31pm Tuesday 2:31pm

On the 23rd and 24th of January, 1930, a young astronomer working in Flagstaff, Arizona, scanned a small patch of the night sky. He was taking pictures of star positions, looking for anomalies that would signal movement somewhere at the edge of the solar system. He took the pictures then set them aside, not realizing… »7/12/15 12:00pm 7/12/15 12:00pm

By using the Gemini Planet Imager, an international team of astronomers have captured an image of a protoplanetary disc that shares remarkable similarities with our own Kuiper Belt — though as it was at a much earlier time in our Solar System’s history.»5/28/15 12:40pm 5/28/15 12:40pm

Scientists are mulling over which of two icy bodies NASA's New Horizons spacecraft should visit following its Pluto encounter this summer — provided the U.S. space agency comes up with funding for an extended mission. »3/22/15 9:30am 3/22/15 9:30am

Pluto is about forty times the distance from the Sun as Earth. But the Solar System is over 50000 times that length across, meaning it could be hiding some huge secrets. That's now looking like a small but real possibility. »2/21/12 5:00pm 2/21/12 5:00pm

The Kuiper Belt, the vast asteroid belt of ice and rock that lies beyond Neptune, is home to three objects big enough to be considered dwarf planets: Haumea, Makemake, and our old friend Pluto. And now, we might have found three more. »8/08/11 8:00am 8/08/11 8:00am

Do you want your share of scientific immortality? You can devote your life to mastering your field, examining the mysteries of the universe, and then finally arriving at one great discovery...but according to Stigler's Law, you won't get the credit. »7/13/11 9:30am 7/13/11 9:30am

Beyond Neptune lies the Kuiper Belt, a massive asteroid belt twenty times the size of the one between Mars and Jupiter. In this frigid, unforgiving environment, organic molecules might still survive, suggesting life's building blocks are everywhere in the universe. »11/01/10 2:17pm 11/01/10 2:17pm

Any alien astronomers searching for life-supporting exoplanets could be in for a disappointment if they look at our solar system - the massive amount of dust in the outer solar system could make all the planets except Neptune effectively invisible. »9/23/10 3:30pm 9/23/10 3:30pm

In 2015, NASA's New Horizons spacecraft will reach Pluto and its frosty moon, Charon. But the journey of discovery will just be beginning, as New Horizons ventures out into the Kuiper Belt, made up of icy bodies just like Pluto. »11/12/09 1:33pm 11/12/09 1:33pm

If you're wondering about the sunny view from the Oort Cloud, that vast sphere of debris that surrounds our solar system, here it is. As we told you yesterday, scientists now believe this remote, cold region might house another Earth-like planet. Only it would be frozen. Want to travel a little closer to the sun, and… »2/19/08 7:00am 2/19/08 7:00am